Apparatus for coking petroleum residues



M. H. TUTTLE APPARATUS FOR COKING PETROLEUM RESIDUES Sept. 5 1944.

FiledJuly so, 1941 lNVENTO R ATTORNEY P E PPPDIP PPDIP P .QW 1i m Patented Sept. 5, 1944 APPARATUS FOR COKING PETROLEUM I RESIDUES Y Malcolm H. Tattle, New Rochelle, N. Y., assignor to Max B. Miller '& 00., 1110., New York, N. Y., a corporationoi' Delaware v Application July so,

.2 Claims.

the stills. This isa troublesome and expensive operation If the cracking is not continuedto the end-point, an uncracked residuum, commonly .referred to as pressuretar, is left as a waste product.

It has heretofore been proposed to coke tarry materials by spraying them onto a stationary bed" of coke heated from below. This process has the disadvantage, among others, that the coking operations must be interrupted from time to time in order to remove the coke from the floor of the still. v I I It has also been proposed to preheat the coke and feed it through a zone where petroleum is sprayed onto it. Some of the proposals to this efiect are unfeasible becausethe'massbecomes gummy and sticks to the apparatus; others are impractical because the apparatus is expensive leum residues while avoiding the foregoingdisadvantages. According tomy present invention a petroleum residuein liquid state is ,fed onto the top of a bed of coke which is heated to suit-{ able temperature,- the bed is rotated to con-;

stantly refresh the upper surface thereof with relatively dry particles of coke, and-atthe same time thebed is steadily pushed toward a point of discharge while the surface on which the bed rests is scraped." While the bed -as a whole is fed end and the other refluxing'por tions of the material at a relatively slow rate. The level of the material-in .the drum is maintained constant by means of a weir adjacent the discharge end of the drum. n

Other features, objects and advantages of my 1941, Serial No 404,583...

invention will be pointed out or will become apparent from the following detailed description of one preferred embodiment illustrating my in-' vention,- reference being had to the accompanying drawing wherein:

Fig. l is a horizontal sectionzthrough an appa-p ratus in accordance with my invention;

Fig. 2 is a vertical section through the same apparatus; v 1 7 Fig. 3 is an end view looking toward the lefthand end in Fig. 1;- and I Fig.4 is a cross-section through the drum. g

The apparatus illustrated includes a hollow steel drum lllwhich is mounted through circular' flanges 'II in suitable bearings l2. The ends of the drumare, closed by stationary end sections l3,- l4 fitted to'the drum by packing rings l5 of any convenient construction. The main portion ofthe drum lies within a furnace l6 for heating the contents of the drum to coking temperature, for instance 40y contbustion of gas admitted at H.

the material in the drum toward the discharge end of the apparatus and a screw conveyor 2| is provided for'refiuxing portions of the material toward the end of the apparatus at which pe. troleum residue or the like is introduced. The screw'20 is rotated at higher speed than the screw 2|, for instance by means of a motor 22, chains 23 and 24, and sprockets 25 and 26. It will be understood that instead of driving two like screws at difierent speeds, the same effect canbe obtained by using screws'of different pitch or different capacity and by driving them at the same speed. The screws are located side-by-side in the lower part oftlie drum, and are arranged so that their outer edges scrape the wall of the 'drum. The drum is rotated, for instance by 40 means of a motor2'l, a chain 28, and a sprocket V 29,- at a speedslower than the speed of rotation of either-.of the screws. a

A pipe 3|, mounted in the end section I3, extends into the drum and has ports 32 facing downwardly toward the bed of loose granular material in'the drum. While the pipe 3| is shown as terminating near the inlet end of the drum, it will be understood that this feed pipe may extend further into the drum. It may be desirable to to feeds. relatively large amount of petroleum residue to the bed of coke near the end of the drum,

and a relatively small amount of petroleum residue near the center of the drum. Adjacent the discharge end of the apparatus there is provided 66 a weir 35 which extends across the bottom of.

A screw conveyor 20' isprovided for pushing the:

the stationary section It. The top of this weir lies at a level below the top of the screws. Y The coke which passes over the top of the weir 35 is discharged through pipe 36. I In order to prevent clogging of the material in the discharge end oi-the apparatus, suitable fingers 31 are secured to the screw shafts. The vapors and fixed gases from the petroleum residue are withdrawn through a pipe 38 and the condensible vapors are recovered in any known or convenient manner.

In carrying out my method the drum is filled with granular coke, for instance one-quarter inchin size, up to the level of the top of the weir and the bed is heated to coking temperature, e. g., 1100-1600 F. The drum and the screw conveyors are then placed in operation, and the petroleum residue is fed to the top of the bed'through the inlet pipe 3|. As the operations continue the larger coke particles rise to the top and are discharged over the weir. At the same time new particles of coke are being formed and are grow-. ing in size so that a constant bed of coke is maintained in the apparatus. The temperatures employed, the rate of feed of petroleum residue or the like, the rates of rotation of the drum and of the screw, conveyors can readily be controlled according to the nature of the particular tar treated.

Due to the rotation of the drum, and also to the refluxing action, dry coke particles are con;

The present invention has been described in connection with the treatment of petroleum residues, but it may be applied to the coking of other stantly raised from the bottom of the bed andare spread over the surface of the bed to which 7 the petroleum residue is applied. Since the drum tarry materials such as, for example, coal tars, pressure tars, t'ars from the Duo Sol or other solvent extraction processes, and the like, which are adapted to be separated or decomposed 'by heat into coke and vapors. ticularly adapted for treating low grade tars whatever their source. If these materials are highly 'viscous or-normally'solid they may be preheated to suitable temperature below the coking temperature, for instance, to about 700 -800 F. For simplicity,. the term tar" as used in the claims includes such materials whether obtained from petroleum or from. other sources. J The terms and expressions which have been employed are used as terms of descriptionand not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described, or portions thereof, but it is recognized thatvarious modifications are possible within the scope of the invention claimed.

What I claim is:

1. Apparatus for coking tar comprising a 1'0: tating drum having a discharge end, a furnace housing the major portion of said drum, 9. conduit extending through one end of the drum and adapted to feed liquid material to the interior of the drum, and a pair oi screw conveyors mounted in said drum, one of which is constructed and arranged to feed material in the is scraped by the screws it is not essential that no wet petroleum residue contact the drum in order to avoid the building up of a crust on the metal. Hence a high rate of feed is permissible, and at the same time it is possible to produce practically dry coke.

It will be observed that the rotation of the drum. has a tendency to convey material from one screw to the other, depending uponthe direction and speed of rotation of the shell. Hence,

drum toward the discharge end and the other of which is constructed and arranged to reflux portions of said material.

2. Apparatus ibr coking tar comprisinga rotating drum haying a discharge end, a.iurnace housing the major portion of said drum, a pair of screw conveyors mounted insaid drum, one of which is constructed and-arranged to feed material in the drum toward the discharge end and the other of which is constructed and arranged to reflux portions of said material, a weir adjacent the discharge end of the adapted". to control the level of the material in the drum, I and a conduit extending through the other end of said drum along a plane above the top of said weir and adapted to feed liquid materials to the interior of said drum.

MALCOLM H. TUTTLE.

Indeed, it is par- 

